export declare function multiKeySet<A, B, V>(m: Map<A, Map<B, V>>, a: A, b: B, v: V): void;
/** replace strings in a text according to a relacement map
 * replaced strings must be 'tokens', surrounded by spaces or punctuation
 */
export declare function replaceWords(text: string, replace: Record<string, string>): string;
/** return an array partitioned into possibly overlapping groups */
export declare function grouped<T>(a: T[], size: number, stride?: number): T[][];
/** group an array into subarrays by a key function */
export declare function groupBy<T, K>(a: T[], key: (t: T) => K): Map<K, T[]>;
/** partition an array into two parts by a discriminator function */
export declare function partition<T>(a: T[], partFn: (t: T) => boolean): [T[], T[]];
/** run an carrying function over every element in an array,
 * i.e. an inclusive prefix scan */
export declare function scan<T, U>(array: T[], fn: (a: T, b: U) => U, zero: U): U[];
/** return a new record by replacing values in 'a' with 'b' as a map.
 * values in 'a' that are not in 'b' are unchanged.
 * e.g. {a: "b", x: 9}, {b: 1} yields {a: 1, x: 9}
 */
export declare function mapForward(a: Record<string, string>, b: Record<string, any>): Record<string, any>;
/** return the last element of an array or undefined */
export declare function last<T>(a: T[]): T | undefined;
/**
 * Overlap two arrays, returning the tail of b if a is a prefix of b.
 * Otherwise, return undefined.
 */
export declare function overlapTail<T>(a: T[], b: T[]): T[] | undefined;